I've got a pair of P. Afer's one 13in. and the other is about 14.5in. VERY VERY AGGRESSIVE the ONLY fish I have ever send completely SHRED a pleco anything that swims mid water to top will sooner or later become attacked they don't seem to bother my polypterus but they have killed plecos that stay on the sides of the tank to long, arowanas get DESTROYED, gars, small 9-10in. and under red devils, etc....
VERY secretive SMART fish very wary of their surroundings I have noticed they tend to watch your eyes they look you dead in the eyes and seem to think things thru I have had mine for about a year now and still VERY hard to see if they don't want to be watched they WON'T be watched
MAN I LOVE MINE